You're not alone. Here's why it happens and what to do:
Cause: System files, caches & incomplete iCloud sync can eat up space.
Fix: Restart, offload apps, check iCloud settings, update iOS (if needed).
Last Resort: Backup & restore as new (erase all content first!).
macdatasaviour
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Hidden system files might be using more space than shown or you might have large files cluttering your Mac.
Try this to free up space:
Check "Storage" details in "About This Mac."
Clean up unused files, Downloads, and media.
Optimize storage with built-in macOS tools.
Empty Trash securely.
Why do you need to experiment with installing a different os at first place?
I’ve been dealing with this issue since the recent Sequoia update, but I finally found a solution and got it fixed. It was pretty annoying, but everything’s fine now.
How did i fixed the issue? you can check here.
[MacBook Pro Screen Flickering Issues: Causes and Solutions]
https://techeasyreview.com/macbook-pro-screen-flickering-fixes/